Relative to comparable ANGLE OF VIEW, lets say you do use a 240 lens at f/22 on 4x5. But to get the same angle of view on 8x10, you'd need a 480mm lens - twice the focal length. So to obtain the same depth of field, you'd need to stop down to f/45 instead, if you use the same shutter speed and same film ASA. That's my level of math - 2X this or that ! Actual compositional issues regarding depth of field is something I judge with my eyes and a loupe on the ground glass itself. Hyperfocal theory and "circle of confusion" is a bunch of nonsensical confusion for sure, as far as I'm concerned. By the time you finish fussing with the math, the lighting has changed! I do sometimes employ hyperfocal theory in Med Format usage. But composition with a view camera needs to become a lot more intuitive and second-nature unless you want to risk unnecessary hurdles. Desired degree of magnification in the end use is also a determining factor. It always amused me when someone fussed around all day long trying to nitpick this topic in some studio application, and then had their 4x5 chrome published even smaller in some magazine than their original 4x5 film!
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